1. Technical Field
The present invention relates to a power transmission device and a manufacturing method thereof.
2. Description of the Related Art
In the related art, a power transmission device is disclosed which includes a gear speed reduction mechanism including an input shaft, an input pinion provided on the input shaft, a rotary shaft other than the input shaft, and a gear incorporated to the rotary shaft, and a casing accommodating the gear speed reduction mechanism.
In this type of power transmission device, in the related art, a casing made of aluminum or a casing made by casting is used. Alternatively, for example, in a power transmission device or the like which is used in a food factory or the like, a casing made of stainless steel may be used.